Matsutaro's winning streak continues, in spite of his usual reluctance. He's not motivated because there's no monetary reward for winning. But lo and behold, here comes Kogane, the prissy rich-boy wrestler, who bribes him with irresistible rewards to throw the bout. Will Matsutaro take the bribe? Of course he will!

Season 1

In the not-too distant past, there once was a young man with a huge body. His name is Sakaguchi Matsutaro, a legal adult who still attends junior high school, and has a crush on a teacher, Reiko. One night he and fellow laborer Nishio go on a joy ride in a truck; but ends up crashing into a bath house.

After his arrest and expulsion from school, Matsu’s homeroom teacher takes him to town for job-hunting interviews. But on the way, Matsu learns his crush Reiko-sensei resigned from her teaching post and moved back to Tokyo. After every interview fails, Matsu has an altercation with a professional sumo-wrestler.

Though Matsu got knocked out by sumo wrestler Iwanokuni, he won’t take it lying down. He rushes to the public arena where the sumo troupe is entertaining the crowd, barges onto the ring, and challenges Iwanokuni to a fight. Headmasters of sumo stables take notice of Matsu’s strength.

Matsu goes to Tokyo with the sumo-stable located near Reiko-sensei’s home, because he wants to visit Reiko-san. However, Matsu quickly angers his fellow sumo acolytes and professional senpais with his boorish disrespect.

So Matsutaro got scouted and reluctantly decided to do sumo in Tokyo. But he never wanted to do sumo in the first place, so his motivation-level is zero. He refuses to wake up for morning training. He even slugs his senpai in the end. But the professional sumo-wrestler Inokawa steps in to teach Matsutaro a lesson.

Matsutaro had decided to become a sumo wrestler to impress Reiko, the lady of his dreams. But he's still not all that enthused about the whole idea. One evening he spends some time with a wrestler-to-be, Tanaka, who happens to be laid out with a cold. They play chess together and Matsutaro in a tantrum makes him cry; feeling bad for that, Matsutaro decides to help Tanaka make the beds for their stable-mates. Boredom sets in after the stable-mates return, so Matsutaro says they should pull a prank on the ani-deshis upstairs.

Matsutaro hasn't let up with his rowdy ways. His debut wrestling match is coming up, and yet, he snores loudly while he waits in the preparation room. Tanaka's debut is coming up too, but Tanaka is frozen stiff with tension. Matsu decides to pep him up, which only leads to more chaos in the auditorium

Matsutaro is officially a sumo wrestler, having made his aggressive debut. But his rowdiness hasn't subsided, not one bit. When his senpais decide to throw a party for the ailing master of Raijin stable, Matsutaro is not invited; though Tanaka is invited, he decides to stay with the rejected outcast, not because he feels sorry for him, but because his master told him to keep Matsutaro out of trouble.

The professional wrestlers of the Raijin stable are racking up their wins, and so is Matsutaro for that matter. But as to the beginner-level wrestlers, their nerves are getting the best of them; none of them are winning.

Matsutaro has been on a winning streak, but Tanaka on the other hand hasn't had a single win. Unexpectedly, Matsutaro volunteers to be his training partner. And another unexpected event: Tanaka's father comes to watch him wrestle in a critical bout.

Inokawa, the only one wrestler who is stronger than Matsutaro at the Raijin stable. He's winning one bout after another. What's his secret? His secret is "White Star," his lucky cat. Superstitious as he is, he starts losing after Matsutaro chases the cat away. Inokawa posts a reward for finding his cat. Now Matsutaro is hot on the cat's trail.

Matsutaro's winning streak continues, in spite of his usual reluctance. He's not motivated because there's no monetary reward for winning. But lo and behold, here comes Kogane, the prissy rich-boy wrestler, who bribes him with irresistible rewards to throw the bout. Will Matsutaro take the bribe? Of course he will!

It's been two weeks since Matsutaro's debut bout, and the day has finally arrived: the final day of the season. Undefeated Matsutaro's championship is riding on it, but he's up against Kondo, another undefeated wrestler. Matsutaro has more horse power than Kondo, but Kondo is an all-around master technician. They don't like each other either. But come what may, it's time for a showdown.

Matsutaro won the Makushita championship, but he's bummed that he doesn't get to be in a championship parade. He wants to get in a convertible, get cheered on by festive onlookers, and drive by Reiko's house. He wants a parade, darn it, and if he doesn't get it, he's shaving his hair and retiring from sumo! The master and Matsutaro's buddy Tanaka are aghast. Is Matsutaro going to shave his head and quit, or what?

Matsutaro hasn't been home since he joined the world of sumo. He decides to go back to his province on occasion of having won the Makushita-level championship. He's greeted by his five siblings who grown quite a bit since he'd last seen them, and of course by his mother.

Sumo wresters working hard throughout the season look forward to touring the country. This time around they're going to Osaka on a sumo train equipped with a restaurant and a viewing car. Matsutaro was looking forward to the trip too, but the sumo world has its strict hierarchy.

The Raijin stable is on tour in Osaka. They don't stay in a hotel but in a temple. Not to mention temples have cemeteries. Tanaka is scared of ghosts so he can't stand it. Takinokawa-zeki sends him on an errand, so he's glad to get out.

Tanaka just can't get strong. If he continues this way, he'd have to retire early, he won't make a living with sumo. Matsutaro, worried about Tanaka's future, thinks of an idea: Tanaka can open a "Chanko" (sumo stew) shop! Even if he fails at sumo, if he could open a first-rate chanko restaurant, his future would be secure.

Sponsors are the financial backbone of sumo stables. Raijin stable's sponsor is the chairman of the board and administrator of a huge hospital, Ueda-sensei. Master Raijin, Inokawa and Tatsunokawa get invited to Ueda-sensei's daughter's wedding, but the two main wrestlers are in Hawaii on a sumo-tour. Master decides to take Matsutaro to the wedding instead, but ... what a dangerous decision for the master to make.

The wrestlers of Raijin stable are training hard for the upcoming season, with the exception of Matsutaro, of course. He meets Reiko at the river while he's fishing, and is invited by her to dinner. Matsutaro thinks he's going on a private date but Tanaka joins them at the restaurant, all gussied up.

Having been dumped by Reiko, Matsutaro spends his days sobbing away under the covers. The rowdy wrestler has withered, and days of peace continue at the Raijin stable. All the wrestlers are glad about that, but they can't very well just leave him alone either. Everyone tries to cheer him up, but Matsutaro is inconsolable.

At first glance it seems Matsutaro had come to his senses after getting berated by Tanaka. He's doing very well this season too, he's defeating one rival after another. Master Raijin and Inokawa feel relieved that Matsutaro is finally getting serious about sumo. But has Matsutaro really changed?

It's the final day of the sumo season. Matsutaro and Kondo are both undefeated. The time has finally come for them to clash; the Makushita championship is at stake. The winner will be promoted to the professional level of Juryo. His mother, siblings, and Shimada-sensei are in the audience. And Reiko is there, too! But where is Matsutaro?